Thanks again for your contributions. Unfortunately I don’t get any technical answer from the video guys.
With a project rate of 23.98 fps the burned in TC is at 1:00:03:14 at the exact Nuendo hour.
With a project rate of 24 fps I stay in sync, and nudging through the frames does not reveal any glitches, although it should, you are certainly right ManChicken. Maybe I the glitch is so small that it is hard to tell, I use a fotojpg converted mov.
As I said, I do not have to do any sync to picture work other than to align music files, around 30 - 120 seconds long. I feel safe using the burned timecode as reference, although it still scratch my head about this discrepancy in the codes. Maybe I get an explanation further on, I will let you know.
Best regards